#pragma once


#include<vector>
#include<iostream>

using namespace std;

static const int __stl_num_primes = 28;
static const unsigned long __stl_prime_list[__stl_num_primes] =
{
  53,         97,         193,       389,       769,
  1543,       3079,       6151,      12289,     24593,
  49157,      98317,      196613,    393241,    786433,
  1572869,    3145739,    6291469,   12582917,  25165843,
  50331653,   100663319,  201326611, 402653189, 805306457,
  1610612741, 3221225473, 4294967291
};

inline unsigned long __stl_next_prime(unsigned long n)
{
	const unsigned long* first = __stl_prime_list;
	const unsigned long* last = __stl_prime_list + __stl_num_primes;
	const unsigned long* pos = lower_bound(first, last, n);
	return pos == last ? *(last - 1) : *pos;
}

enum State
{
	EXIST,
	EMPTY,
	DELETE
};

template<class K, class V>
struct HashData
{
	pair<K, V> _kv;
	State _state = EMPTY;
};

template<class K, class V>
class HashTable
{
public:
	HashTable(size_t size = __stl_next_prime(0))
		:_tables(size)
		,_n(0)
	{ }

	bool Insert(const pair<K, V> kv)
	{
		if ((double)_n / (double)_tables.size() >= 0.7)
		{
			HashTable<K, V> new_HashTable(__stl_next_prime(_tables.size() + 1));
			for (int i = 0; i < _tables.size(); i++)
			{
				if (_tables[i]._state == EXIST)
				{
					new_HashTable.Insert(_tables[i]._kv);
				}
			}
			_tables.swap(new_HashTable._tables);
		}
		size_t hash0 = kv.first % _tables.size();
		size_t hash_i = hash0;
		size_t i = 1;
		while (_tables[hash_i]._state == EXIST)
		{
			hash_i = (hash_i + i) % _tables.size();
			i++;
		}
		_tables[hash_i]._kv = kv;
		_tables[hash_i]._state = EXIST;
		_n++;

		return true;
	}

	HashData<K, V>* Find(const K& key)
	{
		size_t hash0 = key % _tables.size();
		size_t hash_i = hash0;
		size_t i = 1;
		while (_tables[hash_i]._state != EMPTY)
		{
			if (_tables[hash_i]._kv.first == key && _tables[hash_i]._state != DELETE)
			{
				return &_tables[hash_i];
			}

			hash_i = (hash_i + i) % _tables.size();
			i++;
		}
		return nullptr;
	}

	bool Erase(const K& key)
	{
		HashData<K, V>* ret = Find(key);
		if (ret)
		{
			ret->_state = DELETE;
			return true;
		}
		return false;
	}

private:
	vector<HashData<K, V>> _tables;
	size_t _n;
};